Ghasemi-Mobarakeh Laleh, Cano Santiago, Momeni Vahid, Liu Dongyan, Duretek Ivica, Riess Gisbert, Kukla Christian, Holzer Clemens
Department of Textile Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria.
Polymers (Basel). 2022 Sep 2;14(17):3653. doi: 10.3390/polym14173653.
The good interaction between the ceramic powder and the binder system is vital for ceramic injection molding and prevents the phase separation during processing. Due to the non-polar structure of polyolefins such as high-density polyethylene (HDPE) and the polar surface of ceramics such as zirconia, there is not appropriate adhesion between them. In this study, the effect of adding high-density polyethylene grafted with acrylic acid (AAHDPE), with high polarity and strong adhesion to the powder, on the rheological, thermal and chemical properties of polymer composites highly filled with zirconia and feedstocks was evaluated. To gain a deeper understanding of the effect of each component, formulations containing different amounts of HDPE and or AAHDPE, zirconia and paraffin wax (PW) were prepared. Attenuated total reflection spectroscopy (ATR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and rotational and capillary rheology were used for the characterization of the different formulations. The ATR analysis revealed the formation of hydrogen bonds between the hydroxyl groups on the zirconia surface and AAHDPE. The improved powder-binder adhesion in the formulations with more AAHDPE resulted in a better powder dispersion and homogeneous mixtures, as observed by SEM. DSC results revealed that the addition of AAHDPE, PW and zirconia effect the melting and crystallization temperature and crystallinity of the binder, the polymer-filled system and feedstocks. The better powder--binder adhesion and powder dispersion effectively decreased the viscosity of the highly filled polymer composites and feedstocks with AAHDPE; this showed the potential of grafted polymers as binders for ceramic injection molding.
陶瓷粉末与粘结剂体系之间良好的相互作用对于陶瓷注射成型至关重要，并可防止加工过程中的相分离。由于高密度聚乙烯（HDPE）等聚烯烃的非极性结构以及氧化锆等陶瓷的极性表面，它们之间不存在合适的粘附力。在本研究中，评估了添加具有高极性且对粉末具有强粘附力的丙烯酸接枝高密度聚乙烯（AAHDPE）对高填充氧化锆的聚合物复合材料和原料的流变学、热学和化学性能的影响。为了更深入地了解各组分的作用，制备了含有不同量HDPE和/或AAHDPE、氧化锆和石蜡（PW）的配方。采用衰减全反射光谱（ATR）、扫描电子显微镜（SEM）、差示扫描量热法（DSC）以及旋转流变学和毛细管流变学对不同配方进行表征。ATR分析表明氧化锆表面的羟基与AAHDPE之间形成了氢键。如SEM观察所示，在含有更多AAHDPE的配方中，粉末与粘结剂之间的粘附力得到改善，从而实现了更好的粉末分散和均匀混合。DSC结果表明，添加AAHDPE、PW和氧化锆会影响粘结剂、聚合物填充体系和原料的熔融温度、结晶温度以及结晶度。粉末与粘结剂之间更好的粘附力和粉末分散有效地降低了含有AAHDPE的高填充聚合物复合材料和原料的粘度；这表明接枝聚合物作为陶瓷注射成型粘结剂的潜力。
